Depending on functions of treating laundry (objects to be washed), washing machines can be classified into a washer and a dryer. A washer performs a washing operation of removing contaminants from objects to be washed using washing water, and a dryer performs a drying operation of removing moisture from the objects to be washed. Recently, a washer provided with an integrated drying function is under development.
Meanwhile, washing machines can be classified into a top loading type and a front loading type. In the case of the top loading type, the introduction port through which the laundry is introduced is provided on the top of the cabinet. In the case of the front loading type, the introduction port through which the laundry is introduced is provided at the front side (or lateral side) of the cabinet.
The top loading type washing machine includes a cabinet forming the external appearance of the washing machine, an outer tube provided in the cabinet, and an inner tub provided in the outer tub.
In the case of the top loading type washing machine, the outer tub is arranged perpendicular to the ground, and the inner tub is arranged to rotate about a rotating shaft perpendicular to the ground in the outer tub.
In addition, positioned at the top of the cabinet are an introduction port for introduction of laundry into the inner tub, and a cover provided with a door to open and close the introduction port.
The top loading type washing machine performs washing or drying of the laundry through rotation of the inner tub. However, if the inner tub rotates with the objects to be washed non-uniformly distributed in the inner tub (e.g., in the case that the inner tub rotates in an unbalanced state), the inner tub vibrates.
In this case, the inner tub may collide with the outer tub. When the inner tub collides with the outer tub, the outer tub may in turn collide with the cabinet, resulting in separation of the cover from the cabinet or causing the door provided to the cover to open.
In addition, when vibration by rotation of the inner tub is transferred to the outer tub and the cabinet, loud noise may be produced, and the washing machine may even fall over depending on the extent of vibration.